Was Lina Kaufman strangled or is her death a medical mystery?

Produced by Lisa Freed [This story first aired on Oct. 27, 2012. It was updated on June 22, 2013.]

AVENTURA, Fla. -- "I think about Lina every day. ... She was stunningly beautiful. She had class, elegance, style," said Adam Kaufman.

The death of 33-year-old Lina Kaufman in the early morning hours of Nov. 7, 2007, came without warning. The mother of two was living with her husband, Adam, in a wealthy suburb of Miami.

"This particular morning, it was about 5 o'clock. ... I remember waking up ... and seeing her not there. ... And I figured, OK, you know, she's with the baby. She's not in bed, she's with the baby," Adam told "48 Hours" correspondent Erin Moriarty.

"Right around 6 o'clock, I woke up again. She wasn't there. That's when I got a pit in my stomach. ... I remember calling. No response. I remember walking into the bathroom and seeing her there ... slumped over onto the magazine rack."

"When I got there ... Adam ... was at the top of the staircase ... Completely distraught. I've never seen him that way before in my whole entire life," said Adam's identical twin brother, Seth Kaufman.

"Eighteen months later was like a second death in the family," Seth continued. "A SWAT team came in with laser pointer rifles and threw Adam on the floor and arrested him."

Elaine Kaufman never imagined it would come to this -- that she and her close-knit family would be snubbed in their own community, an affluent suburb of Miami.

"I hear whispering when I go places," she explained. "Some people just ignore you. Some people don't wanna hear from you. "

"There are people in this town who think your son is a killer," Moriarty told her.

"Let them think what they want to think," Elaine Kaufman said. "And we're gonna show everybody that he's not."

Adam Kaufman, a successful real estate executive, husband and father of two, now found himself branded a murderer.

"You gotta be kidding me. How could this happen?" he told Moriarty.

But there are the photos taken after Lina's death that show marks on her neck. And in April 2009, a year-and-a-half after he says he found his wife unresponsive in their home, Adam Kaufman was charged with strangling her.

The news of Adam's arrest and Lina's death shook everyone around them -- it simply didn't fit with the couple they knew.

"She was his soul mate," Seth said. "...they were just amazing together."

Did you ever see anything that concerned you about their marriage?" Moriarty asked Elaine Kaufman.

"Never. Never," she replied. "I saw them all the time. They were happy. They -- they loved each other."

Friends and family searched back in their minds. Did they miss something? Lina's mother, Frida Aizman, remembers a strange conversation she had with Lina just two months before her death.

"She said, 'Listen. If something happened to me, I want you to know that I trust my kids only to you,'" Aizman recalled. "I don't know why she ask me. I don't know what -- what her thought was in this moment."

But Aizman says there was no sense that anything was wrong on Nov. 6, 2007. She saw her only daughter at work at the family's upscale furniture business, never dreaming it would be the last time.

"I said, 'You look so beautiful, so classical.' And she said, 'Are you proud of me?' I said, 'Of course,'" Aizman told Moriarty.

"And how would you describe her mood?"

"She was very, very, very happy," Aizman replied.

At the time, Lina, Adam and their kids lived right around the corner from Adam's brother, Seth, and his bride-to-be, Raquel.

"Was Lina excited about the wedding?" Moriarty asked Adam.

"She was so looking forward to it," Adam said. "She was-- one of Raquel's bridesmaids. I was Seth's best man. She was her happiest."

That evening, Lina got a spray tan - her first - to prepare for the big day. On the way home, she visited a friend to show off her tan, have a glass of wine and a bite to eat. Adam was home, he says, taking care of 5-year-old Haley and 2-year-old Jake.

"So I remember her coming home around 11:00," Adam told Moriarty.

"Did you see her when she came home?"

"Yes. Yes, I was already in bed watching TV," he replied.

According to Adam, Lina undressed. "And you could definitely tell she was spray tanned. It just seemed a lot to me," he noted.

They went to bed and the next time Adam says he saw his wife was in the early morning hours of Nov. 7, 2007; she was in this bathroom, he says, slumped over the magazine rack.

"I remember going to -- over to her, seeing all this red stuff all over. Pink, almost frothy whatever it was," he explained. "And I remember grabbin' her from the back. And she felt cold.

"Lina, Lina, Lina, wake up," he continued.

At 6:10 a.m., Adam called 911:

"My wife is in the bathroom dying... She's on the floor dying.

There's blood. There's stuff coming out of her mouth, there's foam.

She looks pale. She looks sick. She has marks on her neck. I don't know what happened."

The 911 operator instructed him to give his wife CPR.

"Push down on her chest rapidly--30 times," Adam explained. "And then back to breathing into her mouth twice."

911 Dispatcher: I need you to do compressions. OK?

Adam Kaufman: ...21,22,23,24,25,26...

911 Dispatcher: Can you hear her breathing?

Adam Kaufman: No, she's cold. ...

911 Dispatcher: Did something happen? Did she fall?

Adam Kaufman: No. No... Oh my Go--Lina ...

911 Dispatcher: Calm down sir, help is on the way, OK?

"You told the operator there were marks on her neck. Where were those marks?" Moriarty asked Adam.

"Here, here," he replied, pointing at his neck. "There were maybe three or four of 'em that I could see."

It would take fire rescue teams 16 minutes to find the Kaufman home.

"They were frantic," Adam explained. "Putting something over her face, putting something in her mouth. ... Continually asking me questions about -- her health. ... I'm thinking, OK, what health problems does she have? Lina was always healthy to me."

Seth and Raquel raced over to help Adam and his children.

Seth Kaufman told Moriarty," We got there and they were working on her in the bedroom at that time. ... it was just an awful scene. It was just tough to --to -- to look at."

They couldn't save her. Lina Kaufman was pronounced dead at the hospital.